Previously, pancreatic mucinous cystic tumors were classified as either benign (cystadenoma) or malignant (cystadenocarcinoma). Descriptions of the fine-needle aspiration (FNA) findings of these neoplasms have heretofore emphasized malignant cytologic characteristics. in the following, we present a summary of a study of FNA characteristics from ten patients with cystic mucinous neoplasms, four of whom have correlating histologic material. in this study, we found a spectrum of cytologic features ranging from completely benign appearing to obviously malignant. We discuss cystic mucinous pancreatic tumors and the associated FNA findings helpful in diagnosis and categorization of these neoplasms. Also, we suggest the inclusion of a new entity in the mucinous neoplasm category. © 1995 Wiley- Liss, Inc.